Means for utilizing exhaust-steam.



APPLICATION FILED JUNEZB, 1909.

Patented May 19, 1914;

o utomatlc Valve Balanced Winesses. Inventor:

- a ugustHKruesi, I 54 4; Mfi

UNITED STATES IATENT OFFICE.

Aueusrjn-l xnunsr,

MEANS FOR UTILIZING EXHAUST-STEAM.

To allwhom it may concern.-

Be'it known that I, AUoUs'r H. KRUESI, a citizen of the United Stat es,residin at Schenectady, county of Schenectady, tate ,5 of New York, haveinvented certain new and useful Improvements in Means for UtilizingExhaust-Steam, of which the following is a specification.

In some power stations having reciprocating and other engines relativelylarge losses occur due'to the inefi'ective use of the low pressuresteam. This is particularly true of stations having non-condensingunits.

My invention has for its object to improve the economyof such stationsby more completely utilizing the exhaust steam, and for a considerationof what I believe to be novel in my invention attention is directed tothe accompanying description and claims appended thereto. a

In the accompanying drawing I have shown more or less diagrammaticallyin Figure 1, one of the embodiments of my invention. Fig. 2 is adiagrammatic view of a motor for operating the valves and a speedgovernor for controlling it. i

1 indicates a mixed pressure elastic fluid turbine which may be of anywell known construction. I have shown one of the Cur- 80 tis condensingtype, because it is particularlyuseful in-this connection. It has aplurality of stagesfour-in the particular embodiment shown. Each stageincludes a wheel 2 having one or more rows of buckets 85 3, two beingshown. Between the rows of wheel buckets are stationary or intermediatebuckets 4 acting to reverse the direction of the motive fluid anddischarge 'it at the proper angle. Steam is admitted to the first 4Qstage by a nozzle 5 and toeach of the subsequent stages by a stagenozzle 6 carried by a diaphragm or other fixed part of the turbine. Theexhaust from the turbine passes by the conduit 7 to the condenser 8.

The admission of steam from the boiler or other source of supply to theturbine is controlled by one or more valves located in a steam chest 9and responsive to a speed governor 10 that is driven by the turbineshaft. 5Q Each valve has a stem 11 that is attached to a lever pivotedat 12 and actuated by a cam mounted -on the cam shaft 13. Each valve isgiven a constant closing tendency by a coiled com ression s ring 14. Thecam shaft is moved y a suita 1e means, such for I Specification ofLetters Itotcnt. Application filed June 28, 1908. Serial No. 504,676.

or SGHENEGTADY, NEW YORIL1$SIGNOR r0 GENERAL ELECTRIC comrAnY, Aconroaanolv '01? NEW Yong.

Patented May 19, 1914.

example as a hydraulic motor 15, rack 16 and gear 17 The movements ofthe motor piston are controlled by a pilot valve 18 and a the latter ismoved by the speed governor 10.

Mounted on top of the turbine is a generator 19 of any approvedconstruction. I have Eshown a vertical shaft turbo-generator unit lbutobviously it can be a horizontal unit if ideslred. The selection of thetype and ar- =rangement of the unit will depend largely :upon thecharacter of the power station and the work to be performed. Steam fromanother source, in this case the main or auxiliary header 25 which.receives steam from one or more agents such as reciprocating engines orturbines 26, is admitted to an intermediate stage of the turbine.Assuming a four stage turbine the pressures at full load may be asfollows: admission 165 lbs. absolute, first stage 52.5 lbs. absolute;second stage 15 lbs. absolute; third stage 4.8 lbs. absolute and thefourth stage 1 lb. absolute. I am giving these figures as illustrationsmerely and not as limitations of my invention because other pressuresmay be utilized. As the load on the turbine decreases the stagepressures will decrease not quite in direct proportion to the load butnearly so, so that at no load a very good vacuum will exist in allstages. The pressure in the header will vary somewhat with changes inload on the said agent or agents. Assuming for example the pressure tobe about 18 lbs. absolute, a part of the steam will pass to the steamconsuming agent 2a which may be a low pressure turbine, or as shown afeed water heater of the open type. The remainder of the steam passes bythe pi e 27 through various regulating devices an the nozzle 6 to thesecond stage of the turbine.

The heater 24; is provided with an exhaust pipe 28 that is open toatmosphere and contains a back pressure valve 29 which is loaded to holda certain definite pressure in the heater-say three pounds aboveatmosphere for example. A valve controlled vent pipe LEO-openin toatmosphere is also provided through w hichthere is a constantcirculation ofsteam to avoid air being pocketed in the heater.

31 indicates a separator lubricating oil-from the'exhaust steam from theheader. Such a device may also be in- I cluded in the piping leading tothe turbine.

In the pipe 27 leading to the turbine is a for separating combined checkand stop valve 32. This valve is opened by pressure from the header whenthe stage pressure falls below a certain value, and is closed bypressure on the turbine side when the stage pressure exceeds that in theheader. The valve is provided with a screw threaded stem and hand wheel33. The lower end of the stem limits the upward or opening movement ofthe valve, and by screwing the stem downward by the wheel the valve canbe positively closed. On the left of the said valve is a butterfly valve34 that is under the control of the speed governor 10. On the valve-stemis an arm 35 that is attached-by the link 36 to the lever 37. The leveris operated by a cam located on the cam shaft 13 which is turned by themotor. This cam is so set that it opens the valve 34 in advance of themain nozzle valves and closes said valve after them. In other wordswhatever be the character of the valve mechanism regulating theadmission of live steam to the turbine this butterfly valve precedes itin opening so as to insure a free passage or opening for the exhauststeam from the header 25. If the load on the turbine is small enough tobe handled solely by .the steam from the header thisvalve will for thetime being act as the turbine regulator, opening and closing as the loadchanges. Under this condition the valveor valves admitting live steamwill be closed. For somewhat greater loads the admission valve OrValvesmay be opening and closing so that a; oer:- tain amount of live steam isentering the machine. Between the butterfly valve and the header is anautomatic pressure responsive regulator 38. This regulator comprises avalve 39,.a diaphragm 40 and a spring or equivalent device 41 that actsin opposition to the pressure from the header. The upper side of thediaphragm'is exposed to the pressure on the turbine side of the valvethrough passage 42, and the under side to atmospheric pressure.

The valve39 is so arranged as to be balancedhigh pressure turbine to theextent of providing it with an opening to receive low pressure steam Ican convert it into a mixed as nearly as possible. Inthis embodiment ofmy invention the balance takes place at atmospheric pressure or slightlyabove this pressure as determinedby the setting of the spring 41.

An advantageous regulator shown is that the diaphragm will be normallycovered with water and will keep cool, hence rubber can besatisfactorily employed- Further this arrangement elim .i nates stufiingboxes and so makes a sensitive device and one free froxnfriction.

Assuming the steam pressure in the headerto be 18 lbs. absolute persquare inch and that in the second stage of the turbine or other pointof admission 15 lbs. absolute or less, the valve 39 of the regulatorwill open and permit steam from the lieader'to flow through thebutterfly valve and the check I feature of .the form. of

turbine will require no from the header drops below that of the sec- 0ndstage, the pressure of the atmosphere on the diaphragm plus the forceexerted by the spring 41 will close the valve 39 of the regu-.

'lator and the turbine will be operated wholly by steam from the boiler.I

It is important to have an automatic pressure regulator to control theflow of steam from the header .to the turbine for without it the vacuumdue to the condenser would under certain load conditions cause a drop inpressure in the heater, and if sufliciently great the water inthe heaterwould boil violently and cause disturbances which are undesirable. Italso preventsair from leak: ing into the turbine and condenser from thelow pressure piping and auxiliaries andimalring the vacuum. The checkvalve is also important because it prevents steam from the turbinepassing'into the heater or other auxiliary when the pressure in theconnected stage of the turbine rises above the predetermined value aswould be the case at loads 1 greater than the rated load or when theturbine' is operating noncondensing above about half load.

Thebutterfly valve in addition to its use or function as a regulatorunder light load conditions of the turbine acts as an emergency valve toshut off steam from the header and prevent the turbine from racing. Ifdesired this valve can also be tripped by the emergency governor of theturbine by.

causing it to release the connection between,

. the valve and lever'37.

It will be seen that by only modifying the pressure turbine. By reasonof this arrangement instead of discharging the steam not required forthe feed water heater intothe atmosphere where it would be wasted, it isdischarged into the, turbine and performs useful work therein also thatby using steam in this way I am able to take advantage of the greaterpressure difference due to the condenser. Whatever steam is ad-- mittedto the turbinein this manner results in a direct saving in the cost ofoperation because less live steam will be required. Under someconditions it is evident that the drive its load. K

I have shown my invention in connection live steam at all towith Miimpulse multistage turbine but it is evident that it can be used inconnection witha reaction type of turbine or a combination of theimpulse and reaction, types.

The particular stage to which the .lo w pressure steam is admitted willdepend upon the ratio of steam required to drive the auxiliaries to thatrequired for feed water heating, and this in turn depends upon theefiiciencies of the auxiliaries, design of the station, manner ofoperating it, nature of the load the station carries, etc.

I have shown only one connection to the turbine but I may use two ormore and in this way utilize steam from several independent sources atdifferent pressures, making similar connections to different stages ofthe main turbine having appropriate pressures. The reason for this isthat auxiliary engines in a power station require an amount of steamwhich does not fall off very rapidly as the load on the main unit whichthey serve is reduced. In-consequence, below a certain load on the mainunit there will in general be too much steam for the auxiliaries andabove this load there will usually not be as much as might be utilizedfor heating the feed water.

I have referred to using exhaust steam from reciprocating engines but myinvention is of Wider application. For example I can use the exhaustfrom relatively small low speed turbines operating non-condensingthrough a relatively small pressure range. Such turbines may be built ata moderate cost and may be direct connected to auxiliary apparatus, 2'.8., centrifugal pumps, blowers or fans, stokers, exciters or otherapparatus. By reducing the pressure range of theauxiliary turbines theymay be made to operate at the desired lOW speeds, andby using theirexhaust in the manner set forth the efficiency of the power plant as awhole will be high. It will thus be seen that I am using the term lowpressure steam in the sense that it is steam which has given up some ofits energy to other apparatus before it finds its way into the turbineas distinguished from live steam or that direct from the boiler.

In accordance with the provisions of the patent statutes, I havedescribed the principle of operation of my invention, together with theapparatus which I now consider to represent the best embodiment thereof;but I desire to have it understood that the apparatus shown. is onlyillustrative, and that the invention can be carried out by other means.

\Vhat I claim as new and desire to secure by Letters Patent of theUnited States is:

1. In combination, a steam consuming agent, a conduit receiving theexhaust therefrom, a turbine receiving steam from the conduit and fromanother source, an automatic pressure responsive regulator in theconduit which opens when the pressure in the conduit exceeds that in theregion in the turbine into which the conduit discharges and closes whenthe pressure falls below a certain value, and an automatic pressureresponsive means arranged between the reg ulator and the turbine forpreventing steam from the turbine from passing through the conduit whenthe pressure of said region exceeds that in the conduit.

2. In combination, a steam consuming agent, a conduit receiving theexhaust therefrom, a turbine receiving steam from the conduit, aregulator in the conduit comprising a balanced valve Which is exposed onone side to conduitand on the other side to turbine-pressure and adiaphragm for actuating the valve, one side of which is exposed toturbineand the other side to atmosphericpressure, and a check valve inthe conduit between the regulator and the turbine that opens toward thelatter.

3. In combination, a steam consuming agent, a conduit receiving theexhaust therefrom, a condensing turbine receiving steam from theconduit, a valve mechanism for regulating the admission of live steam tothe turbine, a speed governor for controlling said mechanism, a valve inthe conduit, a motor controlled by the governor for actuating the valvemechanism and valve, and a self closing valve for preventing the turbinefrom supplying steam to the conduit when the pressure therein issuperior to that in the conduit.

4. In combination, a steam consuming agent, a conduit receiving theexhaust therefrom, a condensing turbine receiving steam from. theconduit, a valve mechanism for regulating the admission of live steam tothe turbine, a speed governor for controlling said mechanism, a valve inthe conduit, means controlled by the governor for actuating the valve,and an automatic regulator in the conduit between the agent and saidvalve which is responsive to pressure in the conduit.

5. In combination, a steam consuming agent, a conduit receiving theexhaust therefrom, a condensing turbine receiving steam from theconduit, a valve mechanism for regulating the admission of live steam tothe turbine, a speed governor for controlling said mechanism, a valve inthe conduit, means controlled by the governor for actuating the valve,an automatic regulator in the conduit between the agent and said valvewhich is responsive to pressure in the conduit, and a check valve thatprevents the turbine from supplying steam to the conduit.

G. In combination, a turbine; a condenser therefor, a means forsupplying live steam to the turbine, a source of exhaust steam whichsupplies steam to a region of interanism by means of which the admissionof live steam to the turbine is overned, valve mechanism by means ofwhich the supply of exhaust steam to the turbine is governed, a speedgovernor that is common to and controls both of said valve mechanisms,and a pressure regulator that is independent of both valve mechanismsand the governor which prevents the vacuum due to the condenser fromworking back to the source of exhaust steam. t

7. In combination, a turbine, a steam consuming agent that exhausts intothe turbine, a controlling valve that regulates the admission of highpressure steam'to the turbine, a valve that regulates the passage of lowpressure steam from the agent to the turbine, a means for positivelyactuating said valves and a regulator responsive to the. pressure of low pressure steam that also? controls the flow of fluid between the agentand the turbine, and a valve for preventing the turbine from dischargingsteam into the exhaust pipe of the agent.

8. In combination, a condensin turbine, valve mechanism for governing te supply of live steam to the turbine, a steam consuming agent, aconduit for conveying the exhaust steam from the agent to the turbine,

- an apparatus in unrestricted communication with the conduit andreceiving a portion of the exhaust steam therefrom, a regulator in theconduit and responsive to pressure on the agent side thereof, a valve insaid conduit, a governor that controls the valve and is driven by theturbine, and a checkvalve that opens toward the turbine from theagentfor preventing the turbine from supplying steam to said apparatus.

9. In combination, a high pressure engine, a turbine, a conduit forconveying the exhaust from the engine to the turbine, a condenser,ameans for governing the admission of exhaust fluid from the engine tothe turbine, a regulator in the conduit which is sensitive toatmospheric pressure and to that of'the fluid within the conduit forpreventing the vacuum due to the condenser from affecting the engine, asource of high pressure fluid for the turbine, and a means con trollingthe admission of high pressure fluid when the supply of low pressurefluid is insufiicient to satisfy the requirements of the a turbine.

10; In combination, a high pressureengine, a turbine, a conduit forconveying the exhaust from the engine to the turbine, a condenser, asource of high pressure fluid supply for the turbine, means forregulating the admission of exhaust fluid to the turbine, means forregulating the supply of high pressure fluid to the turbine, aspeedgovernor that is common to and controls both of said means, and aregulator in the conduit which is sensitive to atmospheric pressure andto that of the fluid within the conduit for preventing the vacuum due tothe condenser from affecting the engine.

11. In combination, a mixed pressure turbine having a low pressuresupply conduit and a high pressure supply chest, a condenser, a valve inthe high pressure chest, a valve .in the low pressure conduit, a motorthat actuates both of said valves, a speed governor for the motor thatis sensitive to speed changes of the turbine, and a regulator which isresponsive to the difference in pressure between the atmosphere and thatof the fluid in the low pressure conduit for interrupting thecommunication between the conduit and the turbine when the conduitpressure falls below a certain value.

12. In a steam system, the combination of apparatus employing steam, anexhaust line leading therefrom, a low pressure prime mover and a heaterconnected to the exhaust line, automatically-operated means for insuringthe supply of steam to the heater and means for preventing the flowofair from the heater to said prime mover, substantially AUGUST H. KRUEsIWitnesses:

BENJAMIN B. HULL, IIELEN Onronn.

